Fluid interposer actuator



Jan. 30, 1968 c. s. JACKOWSKI 3,366,321.

FLUID INTERPOSER ACTUATOR Filed April 29, 1965 1st REV. 2nd. REV.

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PULSE ems C) PULSE CHARLES s. JACKOWSKI TORNE Y OUTPUT e) PISTON United States Patent flfice 3,355,321 Patented Jan. 30, 1958 3,366,321 FLUID INTERFOSER ACTUATQR Charles S. .Iackowski, Endicott, N.Y., assignor to International Business Machines Corporation, Armonlr, N.Y., a corporation of New York Filed Apr. 29, 1965, Ser. No. 451,820 7 Claims. (Cl. 234-169) ABSTRACT OF THE DESCLOSURE Record marking apparatus selectively controlled by the application of pressure pulses of fluid to a compression chamber to serve as the interposer between a continuous driving member and the record marking element.

The control of actuating mechanisms, such as document punches, recorders, etc., is generally accomplished by the selective insertion or movement of mechanical interposers operated by electromagnets. Such mechanisms present difliculty when the controlling is to be done by pressure pulses of fluid since the fluid pressure signals are translated into electrical signals. The translation is usually done by an interface mechanism in which the fluid signals operate electrical contacts or move pistons to produce the desired type of output. These units add components and operating delay in a control so that the elimination of an interface unit is highly desirable where possible.

Although pressurized fluid has been employed at document recording, the fluid used has been under relatively high pressure so that the source pressure is used to exert any force necessary for recording. This technique demands valve control devices and correspondingly heavier components, such as valves and duct work. Alternative recording devices have been devised for operating at lower pressures, but these still require the operation of electromagnetic valves, bi-directional fluid flow in the recording device or selective control of a mechanical interposer which must be moved into and out of position by the flow which tend to lengthen the time required per operating cycle.

Accordingly, it is a primary object of this invention to provide an improved mechanism in which low pressure fluid can be used as the operating interposer in a selective control mechanism.

Another object of this invention is to provide a simplitied and reliable device in which the need for complex valves in an actuating mechanism is eliminated.

Still another object of this invention is to provide a recording mechanism which is capable of being directly connected to the output of low pressure, fluid logic systerns for control thereby.

Yet another object of this invention is to provide apparatus in which fluid serves as the interposer for transmitting force and motion from a driving to a driven element.

The foregoing objects of the invention are attained by the provision of a compression chamber for fluid in which are slidably mounted a compressing piston and output piston each having shank portions extending externally of the chamber. One-way or check valve means are provided for supplying fluid to the chamber intermediate the two pistons. The output piston is held in a retracted position by yieldable means when fluid is supplied and the compression piston is forced to an extended position by the fluid. Cam means operate to move the compression piston to its retracted position thus compressing the entrapped fluid. As the fluid pressure increases, the yieldable means is overcome so that the output piston is caused to move by the fluid pressure thereon. Near the end of the compression stroke, the output piston exposes a vent by which compressed fluid is exhausted. Means are provided to positively restore the output piston to its retracted position upon continued rotation of the cam means. Synchronizing means permit control of the time for supplying fluid to the chamber in relation to the rotation of the cam means.

The use of fluid as an interposer provides a mechanism of unusual simplicity and eliminates electromagnets interposing levers used in the prior devices. The invention affords increased reliability because of a decrease in the number of moving parts. The primary advantage of the invention lies in its ability to perform over a wide range of fluid pressures and with either gases or liquids, thus permitting incorporation in conventional fluid logic control systems as a mechanical output device.

The foregoing and other objects, features and advantages of the invention will be apparent from the following more particular description of 'a preferred embodiment of the invention, as illustrated in the accompanying drawings wherein:

FIGURE 1 represents a front elevation view partly in section, of a mechanism embodying the features of this invention;

FIGURE 2 is a timing diagram showing the relationship of the elements of the mechanism shown in FIG. 1 during operation; and

FIGURE 3 is a sectional view of an alternative arrangement of the compression chamber and check valve as shown in FIG. 1 in conjunction with a biasing arrangement.

Referring to FIG. 1, the invention generally comprises a rotatable cam 10 for driving piston-follower 11 in a fluid compression chamber indicated generally as 12, to compress fluid therein and induce movement in output piston element 13. Cam 10, shown as a double-lobed cam, is mounted on shaft 14 for rotation therewith, and has low and high portions 10a and 10b, respectively. The cam is preferably rotated continuously by a suitable source of power. Compression chamber 12 comprises a hole 17 in stationary block 15 in which follower piston 11 and output piston 13 reciprocate. The fit between the elements and hole is held to close tolerance to minimize the leakage of fluid past the pistons during compression.

Block 15 further has an inlet duct 18 formed therein through which fluid may be admitted to the chamber intermediate the two piston elements. The opening 18 is further formed to provide for a suitable check valve such as flapper 19 secured to L-shaped block 16 that is, in turn, secured to block 15. The elongated upper portion of block 16 serves merely as a retainer for piston follower 11. The block also has an opening 20 therein through which fluid is admitted from a source past flapper valve 19 and duct 18 to the compression chamber. Pistonfollower 11 is shown having a shank portion 21 of reduced diameter movable through the upper portion of block 16 into contact with rotating cam 10.

Block 15 is also provided with an opening 23 below the top of output piston 13 which communicates directly with atmosphere or a suitable low pressure sump through which compressed fluid in chamber 17 may be exhausted. With the piston 13 in the position shown, the chamber 17 is blocked from exhausting. Piston 13 may be equipped with a shank portion 24 depending therefrom which may, for example, be used as a punch slidable in a guide block 25 to perforate the record member 26 and move into a mating die block 27. It is to be noted that the shank portion 24 may be of different configurations to perform other functions as required.

At the conclusion of operation, output element is returned to the position shown from its extended or lower level by restore bell crank 30 rotatable about fixed pivot 31. Shank portion 24 of the output piston is cut on the side to receive end 32 of the bell crank therein. End 32 is slightly rounded so as to move freely in the cutout portion during the translatory motion of piston 13. Bell crank 30 is constantly urged in the clockwise direction by tension spring 33 against fixed stop 34. The bell Crank has a cam follower surface 35 thereon which operates in contact with cam 10 so that the bell crank is also forced against stop 34 by the cam rotation. The cam actually accomplishes the restoration of piston element 13 in high speed operation because the spring 33 is incapable of overcoming the inertia of the restore bell crank. It will be seen that, with the bell crank in the position shown by the solid lines, piston 13 is held in a position to block vent duct 23.

Fluid compressed in chamber 17 to serve as the interposer between pistons 11 and 13 may be supplied from any suitable source, such as a pure fluid amplifier. It is preferable, however, that the supply of fluid be deposited in chamber 17 in synchronism with the rotation of the cam so that piston 11 may be forced upward into contact with the low portion of cam 10. Synchronization can be accomplished in conjunction with a pure fluid amplifier by the use of a slotted wheel, as will be explained below.

Although well known in the art, the pure fluid jet amplifier will be briefly explained as used in conjunction with the invention. Fluid is supplied under pressure from a source (not shown) to a port 40 and nozzle 41 to produce a power stream or jet which can be switched to flow from either of outlet ports 42 or 43. Adjacent nozzle 41 on the left side is a control nozzle 45. The control nozzle is close to the power nozzle and substantially normal thereto for directing a fluid stream against the power jet causing deflection of the jet into outlet port 43. Wall 46 adjacent control nozzle 45 is, however, set back from the wall of nozzle 41 so that the power stream initially attaches itself to wall 46 when started and will flow from port 42. The stream remains attached to the wall until a control stream issues from nozzle 45. At this time the power stream transfers to outlet port 43 and flows therefrom as long as the control stream subsists. The opposite wall 47, however, is not set back at nozzle 41 so that the stream will not attach itself when switched. The amplifier is thus monostable wherein the power stream will remain on wall 46 flowing from outlet port 42 until deflected to the opposite wall and then return, absent a control stream.

Synchronization of stream deflection with the rotation of cam 10 is obtained with a slotted disc 50 mounted on shaft 51 which is, in turn, mechanically coupled to the shaft of cam 10 for rotation therewith. Pressurized fluid, such as air, is continuously supplied in the direction of the arrow to duct 52 from a suitable fluid pressure source (not shown) and the downstream end of the duct directs the air against the input end of duct 53 whenever a slot 54 occurs in disc 50. With each half revolution of disc 50, a pulse of pressurized fluid is supplied to one input of AND duct 55 which is normal to control nozzle 45. The pulse from duct 53, however, is of no effect to the fluid amplifier in the absence of an input signal on the other end of duct 55 via duct 56.

When the fluid pressure is increased by concurrent pulses in both duct 53 and duct 56, the pressure in duct 55 increases generating a control stream at nozzle 45 causing the power stream from nozzle 41 to deflect toward wall 47. The power stream will switch to outlet port 43 which is, in turn, connected by a suitable duct 49 to inlet channel 20 in block 16. The power stream causes flapper valve 19 to open and flows through channel 18 forcing follower pistn'21 upward to the position shown by the solid line. Output piston 13 is held by bell crank 30 and spring 33 so it does not lower during the time the fluid is deposited in chamber 17. Because of the oneway action of flappervalve 19, the fluid is trapped at chamber 17 and channel 18 so that compression of the is forced down by the subsequent compression. A pulse supplied to duct 56 may, for instance, result from pneumatically sensing a punched hole in another record member. The power stream automatically switches back to its original condition adjacent wall 46 when the control stream from nozzle 45 terminates. It is to be noted that a bistable fluid amplifier can be used, if desired, but such an arrangement requires reset pulses from a control nozzle 44, shown in phantom, opposite control nozzle 45 to return the power stream from wall 47 and outlet port 43. Vents 48 are optionally provided to atmosphere or a low pressure sump to prevent the switching of fluid in the event of back-pressure which may overcome the streamwall attachment.

The operation of the fluid interposer mechanism of FIG. 1 will be described in conjunction with the timing diagram of FIG. 2. As stated above, power cam 10 rotates continuously roviding regular and uniform displacement as shown by curve a. When the apparatus is to be selected, a control signal is applied (curve b) by switching the amplifier power stream from outlet port 42 to port 43. This directs fluid into channels 20 and 18 forcing piston-follower 11 upward into engagement with low cam portion 10a. The fluid may be directed to chamber 17 immediately after a high cam portion 1% passes shank 21 of the follower as shown at in the timing diagram. Pulse duration may be 90 or less depending upon the reaction time of the follower-piston. The control piston displacement is shown at curve [I occurring from 90 to Thus, at 180 the chamber intermediate the two pistons is filled with fluid and compression thereof occurs within the following quarter of a cam revolution. Compression forces flapper 1? closed to trap the fluid within the chamber.

Movement is induced in output piston 13 during the compression portion of the cycle and is illustrated by curve e from 180 to 270 of the first cam revolution. From approximately 180 to 210, piston 13 moves down into contact with the record member 26. At that point the piston stops so further compression occurs within chamber 17 because of the increased resistance record 25 adds to the resistance of spring 33. At approximately 240 the force of compression is sufficient to pierce the record and the punch displacement increases sharply. Downward movement of the punch then exposes vent 23 at approximately 255 so that the pressure of the compressed fluid is vented to atmosphere and piston 13 terminates its travel by 270. The bell crank 30 and cam accomplish restoration of the punch from 270 until 360. Control piston 11 remains substantially in the position shown by the broken line because of the exhaust of compressed fluid from the chamber. However, some slight upward movement of control piston 11 may occur. The apparatus has thus completed one punching operation and is ready for actuation again.

Subsequent operations can be accomplished during each half cam revolution. For example, if punching is to immediately occur with the following high cam portion 10b, fluid would have been deposited during the cam movement from 270 to 360 concurrently with the restoration of output piston 13 by bell crank 30. Punching could then occur during cam movement from 0 to 90 of the second cam revolution.

In some mechanisms, it may be desirable to minimize the amount of upward movement of control piston 11 during the restoration of the punch; this can be accomplished by providing a bias force urging the piston down as shown in FIG. 3. A duct 60 communicates with chamber 17 above piston 11 and is connected with a pressurized fluid source. The biasing may be intermittent and alternate with punch control pulses as shown by curve c, or thebias pressure may be continuous. The pressure of the biasing source must, in the latter case, be less than the pressure of the fluid supplied through channels 20 and 13 to drive control piston 11 upward when punching is to occur.

There is also shown in FIG. 3 an alternative embodiment of a check valve which may be used to replace the flapper valve shown in FIG. 1. The check valve is shown as a well-known ball-check valve in which incoming pressure pushes the ball 62 to the position opening channel 20 to channel 18 allowing the influx of fluid. As soon as compression starts to occur by the downward movement of control piston 11, pressure of the fluid forces the ball toward the lower pressure fluid of channel 20 thus trapping the deposited fluid. A cylindrical disc, instead of a ball, can also be used.

It will be recognized that the fluid interposer mechanism shown is not limited to punching but can easily be adapted for the selective transmission of motion by replacing the punch element with a link, lever, print element or the like. The invention, by its arrangement, readily lends itself to incorporation in machines requiring a plurality of adjacent, parallel mechanism. Furthermore, the control piston and output piston need not be of circular configuration but may be of different crosssection to permit closer spacing between adjacent mechanisms. In regard to the piston, it will be noted that flexible, preformed diaphragms can be constructed in the chamber block to cooperate with the follower and output pistons to eliminate the need for close piston fits.

While the invention has been particularly shown and described with reference to preferred embodiments thereof, it will be understood by those skilled in the art that the foregoing and other changes in form and details may be made therein without departing from the spirit and scope of the invention.

What is claimed is:

1. Actuating apparatus comprising, in combination:

means forming a compression chamber for fluid;

first and second piston elements each movable between retracted and extended positions in said chamber and having portions extending externally thereof:

means for yieldably holding said first element in its said retracted position;

means including a one-way valve by which a quantity of fluid can be deposited intermediate said elements under a pressure suflicient to force said second element to its said extended position;

rotating cam means engageable with said second element for moving said second element to its said retracted position for compressing said fluid to exert a force sutficient to overcome said yieldable means and move said first element to its said extended position; and

venting means rendered effective by the movement of said first element to said extended position for relieving the compression of said fluid.

2. Actuating apparatus comprising, in combination:

means forming a chamber for compressing fluid;

first and second compressing elements movable in said chamber;

one-way valve means communicating with said chamber for directing fluid intermediate said elements; rotating cam means operable on said first element for compressing the fluid in said chamber sufficiently to produce movement of said second element; and means for venting said compressed fluid after said second element has been moved a predetermined distance.

3. Apparatus as described in claim 2 further including means connected to said second element and operable by said cam means for moving said second element in a direction opposite to that produced by said compressed fluid.

4. Actuating apparatus comprising, in combination:

means forming a compression chamber for fluid;

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an output member slidable in said chamber in response to fluid compressed therein;

an element movable in said chamber for compressing fluid therein;

means including a one-way valve communicating with said chamber for directing fluid intermediate said member and said element;

rotating cam means engageable with said element for moving said element toward said member to compress said fluid and induce movement in said member;

venting means effective after a predetermined movement by said member for relieving the pressure of said compressed fluid; and

duct means connected with said chamber for directing pressurized fluid to bias said element out of engagement with said cam means.

5. Actuating means comprising, in combination:

means forming a chamber for compressing fluid;

an element movable in said chamber between a retracted and extended position;

means for directing fluid into said chamber in a first duct to bias said element to its retracted position;

an output member movable in said chamber between a retracted and extended position;

yieldable means for holding said member in said retracted position;

check valve means having a second duct for admitting fluid into said chamber intermediate said element and said member to overcome said bias and move said element to its extended position;

cam means engageable to move said element to its retracted position from said extended position and compress the fluid intermediate said element and said member to induce said member to move to said extended position; and

means rendered effective by the movement of said member to said extended position for venting the compressed fluid.

6. Apparatus as described in claim 5 wherein said yieldable means is operable by said cam means to restore said member to said retracted position.

7. Apparatus for marking a record member comprismg:

means forming a chamber for compressing fluid;

a compression element slidable in said chamber;

a record-marking member movable in said chamber from a retracted to a record-marking position in response to fluid compressed therein;

one-way valve means communicating with said chamber intermediate said element and said member for admitting fluid thereto;

means for selectively directing fluid through said valve means;

cam means operable for sliding said element and compressing said fluid to move said member from said retracted to said record marking position;

vent means rendered operable after predetermined movement by said member for relieving the compress-ion of said fluid; and

means operable by said cam means for restoring said member to said retracted position.

References Cited UNITED STATES PATENTS 1,062,580 5/1913 Fils 54.5 1,787,120 12/1930 Noble 6054.5 3,002,678 10/1961 Jackowski 234114 3,022,000 2/1962 Millis 234114 3,282,206 11/1966 Eckert 234107 GERALD A. DOST, Primary Examiner. 

